[Intel-gfx] [PATCH 5/7] drm/i915/guc: Add extra debug on CT deadlock

[John Harrison]

On 12/10/2021 16:56, Matthew Brost wrote:
> Print CT state (H2G + G2H head / tail pointers, credits) on CT
> deadlock.
>
> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
Reviewed-by: John Harrison <John.C.Harrison at Intel.com>

> ---
>   drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> index a0cc34be7b56..ee5525c6f79b 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> @@ -523,6 +523,15 @@ static inline bool ct_deadlocked(struct intel_guc_ct *ct)
>   		CT_ERROR(ct, "Communication stalled for %lld ms, desc status=%#x,%#x\n",
>   			 ktime_ms_delta(ktime_get(), ct->stall_time),
>   			 send->status, recv->status);
> +		CT_ERROR(ct, "H2G Space: %u\n",
> +			 atomic_read(&ct->ctbs.send.space) * 4);
> +		CT_ERROR(ct, "Head: %u\n", ct->ctbs.send.desc->head);
> +		CT_ERROR(ct, "Tail: %u\n", ct->ctbs.send.desc->tail);
> +		CT_ERROR(ct, "G2H Space: %u\n",
> +			 atomic_read(&ct->ctbs.recv.space) * 4);
> +		CT_ERROR(ct, "Head: %u\n", ct->ctbs.recv.desc->head);
> +		CT_ERROR(ct, "Tail: %u\n", ct->ctbs.recv.desc->tail);
> +
>   		ct->ctbs.send.broken = true;
>   	}
>